The present invention relates to data delivery systems and methods. More particularly, the present invention relates to systems and methods for delivering data content over unlicensed radio frequency (RF) spectrum between airborne platform and surface base stations. In some embodiments, this data delivery system may provide data at high throughput data rates exceeding 100 Mbps to enable the transfer of a wide variety of safety, operational and passenger data.
Communication and information access is imperative to the aviation industry. Earliest commercial aircrafts had primitive voice communication with ground personnel over two way shortwave radio. Not only did this communication dramatically improve flight safety, it also enabled accelerated commercialization of air transport on a level not previously known.
Since then, airborne platform have been further upgraded with advent of radar, computers, and even data links to further improve communications. These technologies serve to improve in-flight safety and provide amenities to passengers. However, true broadband high-throughput data uplinks are typically lacking for the airline industry. This is due to a combination of technical and financial constraints which have historically made it impractical, or even impossible, to supply high bit rate data connectivity to an entire fleet of commercial airliners.
However, regardless of hurdles, there is a need to enable broadband wireless communication for airborne platform. This need may generally be broken down into operational needs (i.e., maintenance and repair), air safety needs, and passenger generated needs.
Operational (maintenance) needs are driven by cost savings the airline may recapture by knowing, real-time, the condition of the airborne platform. Gigabytes of flight data are accumulated for each flight but are not easily accessible until after the airborne platform has landed (or are even totally inaccessible if not stored or later retrieval). This renders real time engine trends, fuel consumption rates, and parts performance variances unavailable for timely repairs and cost savings. Some of this data is often discarded because downloading the data currently is too slow or too expensive. In newer aircrafts, such as the Boeing 777 or the Airbus 380, some such operational data may be provided on a real time basis to ground personnel in some cases; however, this data is often limited and relies upon low bit rate speeds. Generally, important operational data is collected and downloaded via a wired access port when the airborne platform has landed. This data collection, however, is not real time data, and cannot be utilized to preplan maintenance needs.
Safety needs include the ability to identify causes and possibly prevent disastrous accidents. Currently, the flight recorder (i.e., “Black Box”) of an airborne platform is accessible after a airborne platform crash. A Cockpit Voice Recorder (CVR) is an audio recorder which is often very useful in identifying causes of the accident. Further, depending upon crash location, the flight recorder and/or CVR are often never found. Without the flight recorder and/or CVR, it may be impossible to determine what caused the crash. Besides satisfying public curiosity and aiding the bereaved, this causal data is very important in generating protocols and/or safety inspections to prevent future similar accidents. Likewise, if critical airborne platform conditions were known by ground personnel in real time, potential disasters could possibly be identified and addressed before they happen. These safety needs are currently unmet given current limited data bandwidth to aircrafts.
Lastly, there are a number of passenger generated needs for larger data bandwidth. For example, unfettered Internet access for passengers could generate high advertising revenues. Likewise, high-speed Internet surfing would facilitate more passenger purchases and commissions for airlines. The limited internet access currently offered by airlines discourages use due to its slow speeds and relative cost.
Those airborne platform that are equipped to provide Internet access, or data communication, typically do so at little more than dial-up speeds. This is due, as stated earlier, to current technological and financial hurdles. One simple approach would be to purchase licensed radio frequency (RF) spectrum to devise a dedicated surface to airborne platform communication network. However such a system would requires substantial spectrum to service an airline fleet and is thus financially prohibitive. For example, it is expected that 160 MHz of spectrum would be required to achieve the desired performance. A recent purchase by Verizon of 14 MHz cost the company between one and two billion dollars. Of course some spectrum is more valuable than others depending upon services envisioned. Cellular and close to cellular spectrum is considered prime spectrum real estate. Regardless, the purchase of the necessary licensed RF spectrum would require an exorbitant capital investment extending to several billions of dollars.
Other approaches to providing data connectivity to aircrafts are to install Satellite Ku Band or Cellular receivers. The weight of a Satellite system is roughly 450 pounds. A cellular system may weigh less, but is still a substantial 125 pounds of excess weight. Weight in an airborne platform is directly related to further fuel consumption. Thus, these systems may cost the airline a lot over the course of their usable lifetimes.
In addition to fuel costs, the units themselves are costly. The cellular system has a substantial cost in the neighborhood of one hundred and twenty five thousand dollars upfront per airborne platform. The cost for a satellite system may be even larger at around four hundred and fifty thousand dollars. Additionally, the cost of maintenance for the satellite system may tack on an additional hundred thousand dollars or so per year per airborne platform, and the array on the airborne platform may, in some cases, extract a substantial aerodynamic penalty.
Additionally, the operational costs of these devices may be very large based upon the size of data being transmitted. It may be costly to send sizable data over satellite or cellular systems.
Lastly, the data rates for common, shared service commercial systems are still relatively low; satellite operates at roughly 1.5 Mbps per airborne platform, and Cellular systems operate between 0.25 and 2.0 Mbps. Further, signal reliability may be of issue for cellular systems. Likewise, satellite bandwidth may be overwhelmed by sudden surges in data download demand, such as may occur if a large number of passengers on a number of airborne platform start data intensive downloads.
Thus, data must be limited in these cases to the point where only a fraction of the above noted needs are capable of being met. For example, the time needed to download a two hour movie may exceed three hours given these technologies. Thus, the existing technologies for data transfer to a airborne platform are woefully inadequate to meet the airlines' needs, even when the funds are available to implement them.
In view of the foregoing, systems and methods for long distance wireless delivery of data are disclosed. The present invention provides a novel system for providing data to or from aircrafts at unprecedented data rates, and in a cost effective manner.